This is awesome! However, this only launches FaceTime, ready to call the selected person. Any way to get FaceTime to automatically press the green FaceTime button to initiate the call? It would be great if we could get FaceTime to automatically initiate the call as well.

I have spent a few hours playing around with ideas to better automate facetime calling. Even though it's not currently scriptable, there are ways around it.
Example AppleScript App:

property defaultCall : "facetimeuser@me.com"
set userInput to display dialog "QuickFaceCall version 0.9.8 Beta" & return & return & "Enter the iPhone number, email address, or AppleID of the person you want to Facetime:" default answer defaultCall buttons {"Cancel", "Call"} default button 2
set ft to text returned of userInput
if the button returned of userInput is "Call" then
tell application "System Events"
open location "facetime:" & ft
-- start AUTO CALL
-- comment the following lines out if you do NOT want AUTO CALL
activate application "FaceTime"
do shell script "sleep 1"
activate application "FaceTime"
keystroke return
-- end AUTO CALL
end tell
end if
end

I have uploaded all of my ideas + source and xcode projects. If you are interested, feel free to download them at:http://www.corndogcomputers.com/tips/facetimepluginsDirect Download: http://cl.ly/3a0bb4f753a2d6ae61b1
You can contact me via twitter @corndoggyrob if you have ideas or comments